The Structure of the Contractile Subunit of the Myofibril Is

question 23

Multiple Choice

The structure of the contractile subunit of the myofibril is called the:

• A) sarcoplasmic reticulum.
• B) actin.
• C) motor end plate.
• D) sarcomere.

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Definitions:

Excavates

A group of unicellular organisms, often flagellates, characterized by a distinct cellular structure, including a feeding groove.

Symbiotic Relationships

Interactions between two different organisms living in close physical association, typically to the advantage of both.

Larger Cells

Cells that are significantly above the average size, which can occur in various organisms and may have specific functional adaptations.

Bacteria

Single-celled microorganisms that can be found in a wide range of environments; some cause disease while others are beneficial.